Process of reducing minerals.



No. 738,007. PATENTED SEPT. 1, 1903 O. B. DAWSON.

PROCESS OF REDUCING MINERALS.

APPLIOATION FILED APR. 16, 1903.

NO MODEL.

@litursscs gnncutnv the metals.

Patented September 1, 190a,

PATENT OFFICE.

OLIVER B. DAWSON, OF CALDWELL, NEW JERSEY.

PROCESS OF REDUCING MINERALS.

SEEGIFIGATION forming part of Letters Patent No. 738,007, dated September 1, 1903. Application filed April 16, 1903. Serial No. 152,856. (No specimens.)

To all whom it may concern.-

Be it known that I, OLIVER B. DAWSON, of Caldwell, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Processes of Reducing Minerals; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The object of this invention is to provide an improved process for reducing and concentrating minerals in the ore into globular, shot-like masses or nuggets, and in which under a continuous feed the ore is first reduced to a metallic spongy condition without allowing the formation of metallic salts and then concentrated and formed into an approximately globular mass of metal within the gangue.

1 am enabled to carry out this process by excluding air and introducing practically pure hydrogen gas for taking off all oxygen, so as to prevent the formation of metallic salts-such as oxids, carbonates, chlorids, sulfids, ciao-and hydrogenizing the elements naturally combined with and extracted from The ore in its natural state and without any flux is passed through a reducing-chamber, where it is subjected to a degree of heat about equal-to that of the be-' ginning incandescence-that is, about- E.,OOO Fahrenheit-the heat being applied externally. While the ore is thus being heated in the reducing-chamber and in the presence of the products of combustion arisfrom the externally-applied heat, which products intermingle with the ore, substanlly pure hydrogen gas is introduced for the purpose of combining with the sulfur, oxygen, and other metalloids present in minerals. The amount of hydrogen must be sli htly in excess of the amount necessary to combine with these metalloids, so that if oxygen should enter with the products of combustion it will combine with the hydrogen gas, preventing the formation of oxids. Thehydrogen hasa stronger afiinity for oxygen than it has for the metals, and it will also take from carbon dioxid part of its oxygen, thereby forming a reducing-gas and at the same time prevent the formation of metallic carbonates, &c. The gases being thus driven off by combining with the hydrogen the gangue becomes cellular, permitting the hydrogen gases to readily and effectively commingle with the minerals, and thereby reduce them to to a metallic spongy condition. Because of the excess in the supply of hydrogen gas there is always sufficient present to maintain the metals in this spongy condition. While still heated and in this spongy condition, the metals pass into a practically air-tight concentrating-chamber,

still in the presence of hydrogen, where theyare subjected to a slightly higher degree of heat than that required in the reducingchamber. The metals being thus fused collect in approximately globular masses after the form of shot or nuggets and may subsequently be readily removed from the fragile gangue by crushing. 0f course, owing to the necessity of the presence of oxygen for the promotion of the combustion necessary to eifect the heating of the ores in the reducing-chamber, a certain amount of CO or CO will have a tendency tointermingle with the ores; but by reason of the excess supply of hydrogen gas no oxide can be produced.- All of the mineral is reduced to a metallic state, the hydrogen gas combining with all the sulfur, oxygen, and other gases or metalloids given oif by the minerals. The amount of hydrogen gas present being in excess of that required for combining with and carrying ofi the gases mentioned enters into the cellular gangue, and thereby freely acts upon the minerals, keeping them in a metallic spongy condition. The gangue is thus made cellular by reason of the withdrawal and consumption of the gases naturally and previously combined with the minerals.

Although my process is applicable to the treatment of various minerals, yet I have found it most advantageous in the treatment of copper-bearing ores and the like.

In the accompanying drawing I have shown in vertical section an apparatus specially applicable for carrying out my process, such apparatus being embraced by my pending application for Patent Serial No. 146,602, filed March 6, 1903.

1 designates the f urnacecasing of approximately air-tight construction; 2,the red ucin ging the direct decomposition of minerals, and

the conversion of the same into globular shotlike masses or nuggets consisting in subjecting the ores without the addition of any flux I thereto, and whileatmospheric air is excluded therefrom, to a continuously-applied external heat for heating the ores to about the degree of beginning of incandescence in the presence of hydrogen gas supplied in quantity in excess of that required for hydrogenizing the elements naturally and previously combined with and extracted from the metals, such excess gas serving to maintain the metal in a metallic spongy condition and preventing the formation of oXids, carbonates, &c., and while still in a metallic, spongy condition, and in the presence of hydrogen gas concentrating the metals in the gangue to globular, shot-like masses or nuggets by subjecting them to a still higher degree of heat in a practically air-tight chamber.

2. The herein-described process for effecting the direct decomposition of minerals, and the conversion of the same into globular, shotlike masses or nuggets consisting in subjecting the ores, without the addition of any flux thereto and while atmospheric air is excluded therefrom, to a continuously-applied exter nal heat for heating the ores to about the degree of beginning of incandescence in the presence of hydrogen gas, together with the products of combustion, such hydrogen gas being supplied in quantity in excess of that required for hydrogenizing the elements naturally and previously combined with and extracted from the metals, such excess gas serving to maintain the metal in a metallic spongy condition and preventing the' formation of oxids, carbonates, &c., and while still in a metallic, spongy condition, and'in the presence of hydrogen gas concentrating the metals in the gangue to*globular shot-like masses or nuggets by subjecting them to a still higher degree of heat in a practically air-tight chamber. r

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

OLIVER B. DAWSON.

Witnesses:

GRAFTON L. MCGILL, FRANCIS S. MAGUIRE. 

